Josh over at Eye for an Eye and Klepsacovic at Troll Racials have both made posts in the last couple of weeks about Paladins and the limitations of mana as a combat 'power' mechanic for the class. They're both well worth reading, and with any luck will be a quality retrospective view of the 'bad old days of TBC' in a years time when we are all playing Wrath. I posted my response on E4aE, but here it is for my own blog:
This issue isn't unique to Ret Paladins, Holy Paladins also suffer from the exact same issue and is a reason why many stack Mp5 over Spell Crit (the other being that it is cheaper budget-wise). To a lesser extent so do so Hunters, and whilst I can't recall if AotV mana regen is hugely significant (i.e. beyond that of BoW), I do know that it is a great concern for them. On the flip-side, JoW roxors their soxors, but the comparisons for 10-man and 5-man encounters still hold.
This of course really comes out of Mana being a broken mechanic for Melee, in fact it's tacitly acknowledged by Blizzard in that DK's have a unique power mechanic and Prot Paladin's mana pool has been fudged into a pseudo-rage pool which can still be mana-burnt. Shaman were pretty much always casters, and Enhancement was thrown a huge amount of scaling mana-regen in the form of Shamanistic Rage to compensate. It's only now, with active damage abilities that we're all starting to clue up on how important mana is for a DPSing Paladin.
On a similar note, Mana Burn is an immense problem which needs addressing, and I feel that they need some form of protection from that mechanic, both for PvE and PvP. But... I don't think they are going to change it. In many ways they will probably utilise it to reinforce the concept of DK's being the premier anti-caster tank.
The problem is, I just don't know what Blizzard would be willing to do about this state of affairs. I have the feeling that they want Paladin mana starvation to be downside for the class as a whole (similar to lack of armour, waiting for energy or... erm... what's the downside to rage again?), meaning that we will continue to have to synergise well with other classes in order to fight for over 5 minutes. This is all very well and good in raids, but absolute balls for 10-mans where arguably a Ret Paladin is weakest. If they were to boost our personal mana regen it would probably be through a significant buff to SoW, to the extent that it procs on every hit and regens 5% of total mana per hit. There are many more interesting ways to boost Paladin Regen for both Holy and Ret, but Blizzard have painted themselves into a corner in limiting the mechanics available to Paladins to such an extent that I just don't see them doing it in a way which doesn't compromise their damage or healing to a non-negligible extent.